Bass DI Problems/Revamping questions

[FevinKraser]

Hello, I don't post here often but I certainly read many things on this forum.

I was having issues the other day recording bass. My plan was to have my bass through a DI box. The DI box would send an XLR out to my mixer, while the 1/4 inch output would travel to my bass amp, which was mic'd as well.

For a reason I don't understand, signals that must have been traveling from my computer through my mixer were being amplified into my amp.

For quick problem solving I ended up not using the amp at all, and recorded through the DI box alone.

Is this a grounding issue with my XLR chords? or is this a computer issue?

I'm really hoping someone could help me out, because I'm looking to do revamping, but this issue is a barrier for that as well. Anything connected to my mixer and my amp will cause this problem.

Thank you so much, even if you are simply reading.

Kevin

[Nick Sevilla]

Hi,

The issue was in one of two places:

a. the mixer was routing signal out to the amp. As in you used an Uax sedn to the amp, and something else was also in the aux signal.

b. the DAW was sending more than just the bass to the output going to the amp.

Since you don't elaborate on the mixer, not it's settings, nor the DAW nor it's settings, these are wild guesses.

Cheers

[FevinKraser]

Sorry, I wasn't sure how to properly explain it. Thanks for lending some of your time.

My mixer is an Alesis Firewire. My DI box is connected to my bass amp, and channel 3 on my mixer. Nothing is being intentionally sent from the mixer to the DI through Aux's, main outs or anything else.

My mixer is connected to my computer via firewire.

I don't know what sort of DAW settings your looking for, but nothing was being monitored from my project.

[Nick Sevilla]

Sorry, I wasn't sure how to properly explain it. Thanks for lending some of your time.

My mixer is an Alesis Firewire. My DI box is connected to my bass amp, and channel 3 on my mixer. Nothing is being intentionally sent from the mixer to the DI through Aux's, main outs or anything else.

My mixer is connected to my computer via firewire.

I don't know what sort of DAW settings your looking for, but nothing was being monitored from my project.

Earlier, you mentioned :

signals that must have been traveling from my computer through my mixer were being amplified into my amp

What were those signals, what were their routings? That's where the problem lies, then. Inside the DAW.

Cheers

[Front End Audio]

What sort of signals are you hearing through the amp? Is it music, or computer noises like beeps and/or whirring?

Also, what DI box are you using? Does it have a ground lift? Have you tried engaging the ground lift? Have you tried other 1/4" and XLR cables?

Another thing to try: Is the computer plugged in to the same electrical circuit as the amp and firewire interface? Depending on the wiring in your recording location, sometimes you can get noise issues if you have your separate pieces of gear plugged in to different circuits.

I hope this helps,
Damian

[FevinKraser]

noeqplease: My DAW wasn't even running. The noises occured when my computer turned on.

Frot End Audio: The noises are amplified computer signals. Beeping and screeching (it was almost musical in a way).

The room I use has only one circuit, so I'll try it in different circuits. I think it does have a ground lift so I'll try that too. I have however gone through every chord i have.

thank you so much for your time. I'll give another try and come back.

Fevin

[suppositron]

Try lift the ground on the instrument cable that's running into the bass amp.

Edit:

Wait, that's probably gonna give you a horrible buzz. I'm pretty sure it's the ground on your computer that's causing the problem. Try lifting it there or on the di like you were saying before and that should fix it.

[Nick Sevilla]

noeqplease: My DAW wasn't even running. The noises occured when my computer turned on.
Frot End Audio: The noises are amplified computer signals. Beeping and screeching (it was almost musical in a way).
The room I use has only one circuit, so I'll try it in different circuits. I think it does have a ground lift so I'll try that too. I have however gone through every chord i have.
thank you so much for your time. I'll give another try and come back.
Fevin

Then the issue is that your computer's CHASSIS GROUND (the box itself and possibly it's motherboard) are tied with the AUDIO GROUND.

I use a Radial dual ( stereo ) DI box between my computer's headphone outputs (where I playback from iTunes / internet) and my mixing console's line inputs. This eliminates the 60 cycle hum that occurs within my Mac Pro tower, since it's audio a chassis grounds are hooked up together, and cannot be decoupled. There are cheaper and just as effective stereo DI boxes that can solve your issue.

This leaves my Pro Tools HD hardware free to have a session open when I am referencing other material for sound purposes.

Cheers

[nortstudio]

I know you mention that the noise is your computer - and it very well may be. Do you have an external hard drive hooked up when the noise occurs? Is it firewire?

I have had similar, strange sounds come from certain audio hard drives when they are plugged into the studio computer - almost sounds like you hear bleeps and blips when the drive is spinning up - and then stays on until you dismount the drive and remove it.

I ask, because if the Alesis is hooked up through firewire, and you have a drive hooked up through firewire, this might be the culprit.

All suggestions about trying different outlets/electric lines from the breaker box are spot on as well.

You need to be systematic about it...

[LastStandStudio]

also hopefully you have an extra XLR you can swap to verify that is or is not the issue. After you verify that try introducing each peice of equipment one by one to see where your issue is. Do you have another output from your DI, give that a shot.